Savory flavors and flavor enhancers, made from flavor bases such as hydrolyzed vegetable protein (HVP), yeast extract, monosodium glutamate (MSG), and nucleotides are added to food products to enhance the existing flavors of food products or to impart additional or enhanced flavors to food products. The savory flavor imparts a spicy, meaty profile to food products containing the savory flavor. Flavor enhancers intensify flavors already existing in a food product. Essentially, the flavor enhancers and savory flavors have a synergistic effect with flavors already existing in a food product so that when the food product is consumed by a person they will more readily taste the flavors found in the food products. Often the savory flavors and flavor enhancers work to enhance vegetable, meat, cheese, and seafood flavors of various products. Among the food products that savory flavor and flavor enhancers are used in are soups, gravies, meats, snacks (such as snack crackers and chips), breakfast foods, and canned and frozen meat products. As such, savory flavors and flavor enhancers are used in a wide variety of food products to enhance taste.
HVP is a savory flavor base often used to form savory flavors and flavor enhancers, with the HVP generally described as either a flavor donor, a flavor enhancer, or a combination thereof. The HVP can be formed by hydrolyzing a vegetable protein with an acid or an enzyme. The protein or raw material used to form the HVP typically includes one of the following: wheat gluten, corn gluten, defatted wheat germ, defatted soy flour, defatted peanut flour, and defatted cottonseed flour. Wheat gluten is often the preferred raw material because it has an increased amount of glutamic acid which will allow often for the production of an HVP that has a less bitter, sweeter flavor. The less bitter, sweeter flavor is similar to a yeast extract, meaning the HVP can be used as a replacement for the yeast extract when formulating a savory flavor base. It is desired to use an HVP as opposed to a yeast extract as yeast extracts are comparatively expensive to produce and use. Unfortunately, wheat gluten can be expensive to use as a raw material. Thus, it is desired to have a more economical replacement, such as an HVP, for a yeast extract.
Defatted wheat germ when used to form an HVP imparts a desired flavor; however, it also suffers from being expensive to use. It is known that defatted wheat germ contains about 30% by weight peptides or protein. As such, typically the yield of HVP from defatted wheat germ is decreased. Conversely, when defatted soy flour is used to form the HVP, the soy flour typically contains at least 50% by weight protein. Because of the lesser amount of protein found in the defatted wheat germ, a lower yield is realized which in turn makes it less economical to use. Another problem associated with defatted wheat germ is that it is a processed product or an "end" product. This will also increase the cost associated with producing an HVP from defatted wheat germ as the raw material has a higher comparative cost than other raw material. It is desired to produce an HVP from defatted wheat germ that has a sufficient yield and is economical to form.
Soy proteins or derivatives from soybeans are typically used to form HVP. Unfortunately, HVPs derived from soy tend to have a bitter flavor that is unsuitable for many savory flavor applications. For this reason, it is desired to produce an HVP from a raw material other than soy. Also, most HVP's, including those formed from wheat gluten and soy, typically have a high salt content. Generally, the salt content in an HVP will range between about 40% and 45%. It is desired to produce an HVP having a lesser salt content.
Acid hydrolysis is currently the most practiced enzymatic method for producing an HVP. In the acid hydrolysis method an amount of acid is mixed with an amount of vegetable protein, soy protein for example, with the acid hydrolyzing the protein. The acids used to hydrolyze the vegetable protein starting material include sulfuric acid and hydrochloric acid, with the hydrochloric acid the most commonly used hydrolyzing agent. When HVPs are made with sulfuric or hydrochloric acid they will typically contain an amount of sodium or potassium chloride as a result of the neutralization process which is performed to adjust the pH of the HVP.
Acid hydrolysis, even though it is the most frequently used commercial method, unfortunately suffers from potentially producing a flavor base having too much salt. Also, acid hydrolysis can impart negative or undesirable flavors to the flavor base, which is an undesired result. It may also be true that acid and/or alkaline hydrolysis can destroy L-form amino acids, cause formation of D-form amino acids, and formation of toxic substances such as lysio-alanine (Lehl and Grindstaff 1989). Recently, it has been shown that the process of hydrolysis using HCl can lead to the production of chloropropanols which are known to be carcinogenic. This is especially troublesome if the savory flavor product is to be marketed in Europe where there are specific limits as to the amount of chloropropanols that can be present in a food product. A further problem is that the acid hydrolysis method can be relatively expensive to perform. Thus, there is a desire for a method for producing HVP products that does not involve an acid hydrolysis process.
It should be pointed out that salt free HVP products can be obtained by using sulfuric acid to hydrolyze the vegetable protein and then neutralizing the HVP solution with calcium hydroxide. This, however, is a comparatively more expensive method. As such, it is desired to have an inexpensive method for providing a substantially salt free HVP.
As mentioned, it is known to also use enzymatic hydrolysis to hydrolyze vegetable protein, with the hydrolyzed vegetable protein then available for use as a flavor base. Enzymatic hydrolysis suffers from typically resulting in incomplete hydrolysis of the vegetable protein and from generation of peptides that impart a bitter taste to the savory flavor. Thus, it is desired to be able to hydrolyze a vegetable protein with an enzyme, whereby the hydrolysis is complete and the finished HVP is not overly bitter.
When enzymatic hydrolysis is performed, a flavor base is produced, with the flavor base having a variety of different flavors and flavor nuances which are dependent in-part upon the specific enzymes selected to hydrolyze the vegetable protein. Thus, different flavors can be imparted to the flavor base dependent upon the enzymes selected to hydrolyze the vegetable protein. Also, HVP flavor bases produced by enzymatic hydrolysis will have a different flavor than HVP flavor bases produced by acid hydrolysis. Soy bean meal or other soy vegetable proteins are used typically to form the hydrolyzed vegetable protein. Like the enzymes or acids, the particular protein selected will influence the flavor of the flavor base. As such, it is desired to have a method for producing different flavors in flavor bases than what is currently known. It is also desired to have a method which does not use a soy protein as the protein for forming the HVP. In particular, it is desired to have a method for producing an HVP that will have a slightly sweet taste, as opposed to a bitter taste.
An example of a typical method used to form an HVP flavor base includes placing 1600 Kg of soy bean meal in a vessel with 1100 Kg of water and 1500 Kg of 30% hydrochloric acid (HCl). The mixture is then heated to a temperature ranging between 100.degree. C. and 120.degree. C. for 2.5 hours at two (2) atmospheres of pressure. The mixture is then cooled to 50.degree. C. and neutralized with 50% sodium hydroxide to a pH of about 5.6, with the pH ranging anywhere from 4 to 6. The mixture is then cooled and filtered to separate insoluble material from a protein filtrate. After this, the protein filtrate is concentrated to a paste and further dried by roller drying, spray drying, or oven drying. Prior to drying, the filtrate can have constituents, such as salt, added thereto, with the dried filtrate then ready to be used as a savory flavor or flavor enhancer. This method will result in a flavor base having a distinct taste or flavor.
In addition to HVP, as mentioned, yeast extract or yeast autolysates can be used as a flavor enhancer and/or a savory flavor. The yeast autolysate is produced from common yeast, Saccharomyces cerevisiae, which are obtained as a bi-product of beer production or may be specially grown in a suitable sugar medium. If the yeast obtained as a bi-product of beer production is used, it is first made into a slurry. The slurry will produce the best conditions for autolysis of the yeast cells by enzymes contained within the yeast cells. As such, enzymes, mainly proteases, cause the breakdown of protein present within the yeast cell to polypeptides and then to amino acids. Once autolysis is completed, a liquor is produced that retains the insoluble cellular material and other unwanted materials, so that the liquor is separated from the remainder of the hydrolyzed material. The hydrolyzed material is then concentrated into a paste or dried to a powder. It is then ready for use as a savory flavor or flavor enhancer. As such, when the yeast autolysates are produced the soluble material is separated from the insoluble material with the soluble material used as the yeast extract. Yeast autolysates will have a unique taste that is different than most HVP products.
In the food industry it is necessary to have a variety of different flavors as consumers more and more demand new and different flavors. For this reason, it is necessary to develop new flavor enhancers and savory flavors, and more particularly, new flavor bases, that have slightly different tastes and characteristics which consumers demand. Thus, it is desirable to have a new HVP that is not formed from soy or by acid hydrolysis, and that has new and different flavors that have previously not been known in HVP products.
Previous methods for producing flavor bases that have been used have suffered from a number of problems including being costly and having undesirable flavors. Thus, a less expensive method for producing HVP is desired. Further, it is desired to have an HVP with different flavors, especially sweeter, less bitter flavors. Also, previous methods have resulted in a product that may contain an undesirable amount of salt, as well as, being potentially carcinogenic. For this reason a potentially more healthful HVP flavor base is desired.